The goal of this project is to identify epithelial cell-derived gene products which are contributing to the pathogenesis of allergic rhinitis, as well as to work out the kinetics of the expression of those gene products. To date, 42 subjects with allergic rhinitis have undergone the screening visit with determination of a provoking dose of allergen and underwent subsequent allergen challenge. Nasal tissue samples were collected at baseline, 8 and 24 hr following allergen exposure. Total RNA was isolated and mRNA levels for specific genes were analyzed by Ribonuclease Protection assays. To date, we have looked at the expression of IL-8, ICAM-1, eotaxin, RANTES, GM-CSF, and IL-16 and the bradykinin receptor, B1. The goal is to identify those gene products which allow for the transition from an early phase response to allergen, to a late phase, more chronic inflammatory state and look at interfering with the transition with various topical agents.